Heating and ventilating system



Sept. 26, 1944.

G. D. SKINNER HEATING AND VENTILATING SYSTEM Filed Feb. 28,

Patented Sept. 26, 1944 NT OFFICE HEATING ANDVENTILATI NG SYSTEM GeorgeDonaldSkinner, London, England Application Februar 28, 1942, Serial No.432,899

H In Great Britain October 13, 1941 4 Claims. (01. 250-43) Thisinvention relates to heating and ventilating systems and moreparticularly to heating and air conditioning units adapted to be mountedon the fac of a wall or suspended from roof or ceiling members of abuilding.

Such units although they comprise heating elements, are usable in warmWeather without the heating elements being in operation so as to providea beneficial circulation of cooling air.

The primary object of the present invention is to provide a convenientunit of this general character which in addition to the normal functionof merely circulating the air, heated or not, has incorporated in itmeans for sterilising the air so circulated from harmful bacteria.

According to the invention this sterilisation of the circulated air iseiTected by subjecting the air in its passage through the unit to theeffects of ultra-violet radiation which can conveniently be efiected bymeans of suitable electric discharge lamps.

The invention may therefore be said to consist in its broadest aspect ofan air conditioning unit comprising a casing having inlet and outletopenings for permitting the passage of air through the casing, a fan forcirculating the air through the casing, a heating element, and means forgenerating and radiating ultra-violet rays positioned so that thecirculated air is subjected to the effect of the rays.

The invention further comprises the employment of electric dischargelamps as the means for generating the ultra-violet rays and the use ofthe windings of an electric motor used to drive the fan to control theelectric discharge lamps whereby the use of the inductive chokes usuallyemployed for this purpose is eliminated.

In the preferred practical application of the invention a three-phasefan motor is employed each of the three windings of which is used tocontrol an electric discharge lamp. If desired an ozoniser of knownconstruction and operation may be incorporated in the unit.

An embodiment of the invention is shown in the accompanying drawing,wherein Figure 1 is a perspective outside elevation of the improvedunit,

Figure 2 is a diagrammatic sectional view thereof, and

Figure 3 is a diagram of the electrical connections.

Referring to the drawing, the numeral l indicates a casing with a frontlouvred opening 2, behind which is an electric heater 3. Centrallyacross the interior of the casing are mounted three electric dischargelamps 4 provided with suitable transparent envelopes capable of passingawave length of 2537 Angstrom units radiation, and at the back of thecasing is the circulating fan 5 driven by a three phase motor 6.

The casing I may be mounted on a wall by a surrounding flange 7 integralwith the back wall of the casing, and as shown in Figure 1 screening orbaille plates 8 may be attached to the side walls of the casing I toassist in directing the flow of discharged air.

The electrical connections for the motor 6 and heating element 3described above are illustrated by Figure 3 in which 9 indicates thesupply mains connected to the three phase motor windings ID. This motoroperates as a pilot motor off a single phase circuit. The heater istapped off from the mains 9 at H likewise an ozoniser, if employed, istapped oiT as indicated by the dotted lines at l2. The three lamps areconnected to leads l3, l4 and I5 and a condenser l6 as shown. Where athree-phase supply is available a standard three phase motor can beused, in which case a lamp would be connected in each phase of the motorwindings.

Although the heating element employed is indicated as an electricalheater it is to be understood that a heater of any form may be employed.

As is well known to those skilled in the art, the efllciency of thesterilizing action of such lamps on air-borne bacteria is highest whenthe lamps ar maintained at about F. It is therefore important, with thepresent apparatus, to locate the lamp in suitable positions in theheater casing where this temperature will be attained or most nearlyapproximated. In cases where the lamps are subject to the coolingeffects of an air stream and the heating effects from a heating element,screening means will be required to ensure the maintenance of asatisfactory working temperature. For example in the arrangement shownin Figure 2 deflectors or screens are arranged to efiect this screeningof the upper and lower lamps while deflectors or screens I6 may bearranged on each side of the central lamp, the deflector on one sideprotecting the lamp from the effects of the air stream from the fan 5and that on the other side protecting the lamp from the effects of theheater 3. The upper and lower of the lamps 4 may need to be shielded byscreens such as IT.

It will be understood that the utilisation of the fan motor windings asballasts for the control of the discharge lamps is not dependent uponborne bacteria.

the use of a three-phase main supply, and is merely a question ofselecting the type of electric motor to suit the mains supply and thenumber of discharge lamps needed in a unit.

If desired, an air filter indicated at l8 may be incorporated with theapparatus, consisting, for example, of fabric treated with an oily oradhesive medium arranged over the inlet openings to the casing I, whichwill be capable of removing not only the larger particles of dirt in thecirculated air, but also the larger sizes of air- The filtered air isthen subjected to the ultra-violet radiation, which will be capable ofdestroying the smaller bacteria thatit is not possible to trap by thefilter.

It will be appreciated that, by suitable spac I quiet about the lampsing of the combined heating, ventilating and sterilizing units, thewhole of the floor area of a room or building may be efiectivelyprovided with a continuous supply of tempered and sterilized air which,whilst providing any desired degree of heating or cooling to suit theoccupation of the people in the room or building, will also greatlyminimise the risk of infection and passin the casing is subjected, andscreening devices about the lamps to baffle the air and keep it andavoid chilling the lamps below their proper operating temperature.

- '2. An air conditioning unit according to claim 1, wherein the outletopening from the unit is provided with louvers for directing the air onits disoharge.-

3. An air conditioning unit according to claim l, having a filter in theinlet opening.

'4. An air conditioning unit according to claim 1, having aheatingelement located withinthe casing adjacent the outlet opening;

GEORGE DONALD SKINNER.-

